Strain insulator



July 16, 1929. w. H. PEARL STRAIN INSULATOR Filed Aug 6 1 ATTORNEY,

Fatentecl July 16, 1929.

WILLIAM H. PEARL, or INDIANAPOLIS, NDIANA.

STRAIN INSULATOR.

Application filed August 6, 1924. Serial No. 730,393.

It is the object of my invention to provide a simple strain insulatormounting which can be installed with a minimum of effort and care on thepart of the lineman, and which when in place has its parts eifectivelyinterlocked to prevent their accidental separation; and which isinexpensive and easy to manufacture.

In carrying out my invention, Iprovide two mating members, preferably ofidentical shape so that any two such parts may be used together. Thesetwo members have two fingers, one on each member, for projecting intothe opposite axial ends of the bore of an insulator, with the fingersdesirably overlapping within the insulator bore. Each finger projectstransversely from one end of an arm, which in turn projects from aperforated ear which overlaps a similar ear of the mating member so thatthe perforations register to receive an attaching member, such as ascrew-hook or a staple; The two overlapping ears of the two matingmembers preferably have interlocking parts, such as a finger in oneprojecting into a hole in the other, which interlocking parts co-operatewith the attachin member when the latter is in place in the perforationsof the overlapping ears to prevent suflicient relative movement betweenthe two mating members to prevent either their separation or thewithdrawal of the fingers from the bore of the insulator.

The accompanying drawing illustrates my invention: Fig. 1 is a plan of astrain insulator mounting embodying my invention. with the insulator andthe attaching screw-hook in dot-ted lines; Fig. 2 is a section on theline 22 of Fig. 1; Fig. 3 is a plan of the two mating membersof theinsulator mounting, separated; Fig. 4 is an end view of the straininsulator mounting, showing the overlapping of the fingers within theinsulator bore, the insulator itself being shown in dotted lines; andFig. 5 is a section on the line 55 of Fig. 1.

The insulator 10 is desirably of the usual type of porcelain insulators,with an axial bore 11 and one or more exterior circumferential grooves12; one such groove 12 is shown in the insulator of Fig. 1, and two suchgrooves in the insulator of Fig. 4. The groove or grooves 12 are toreceive in the usual way the wire or wires which the insulator carries.

The insulator 10 is supported on the inwardly projecting fingers 15 ofthe two mat ing members 16 of my strain insulator mounting. The twomembers 16 are desirably of identical shape, so that any two suchmembers may be used together. The two fingers 15 project into the bore11 of the insulator 10 from the opposite ends of such bore, as is clearfrom Figs. 1 and 1. The adjacent ends of the two fingers 15 desirablyoverlap to form an oblique joint 17 within the bore 11, desirably atabout the middle of such bore. Each finger 15 projects transversely fromone end of a supporting arm 18. From the other end of such arm 18 an ear19 projects laterally on the same side as the arm 15 so that when thefingers 15 overlap, the cars 19 will also overlap, and the two matingmembers will form a complete inclosure. The ears 19 desirably overlap inthe reverse Way from that in which the fingers 15 overlap; and are soarranged. that theear-faces which abut are in about the mediallongitudinal plane of the arms 18 and fingers 15.

The ears 19 are provided with holes 20,

which register when the ears 1.9 of two of the mating members 16 are puttogether, as is clear from Figs. 2 and 5. In addition, each ear 19 isprovided with a lug 21 projecting from that ear-face which abuts againstthe mating ear, and with an opening 22 suitably arranged to receive thelug 21 of a mating member when the two members are put together withtheir holes'2O in registry and their fingers 15 overlapping. The lugs 21and holes 22 are eccentrically located with respect to the holes 20, sothat when they are in engagement they prevent turning of the two members16 relatively to each other about the common axis of the two registeringholes 20. Conveniently the hole 22 is merely a lateral extension of thehole 20, at one side, as that facilitates manufacture. In addition, thelugs 21 are preferably of somewhat greater length than the thickness ofthe cars 19, as is clear from Fig. 5, to insure against their separationfrom the holes which receive them.

lVhen two mating members 16 are put together with their holes 20 inregistry and their fingers 15 overlapping, a suitable attaching membermay be inserted through the registering holes 20 to hold them inregistry and to furnish the support for the structure as a whole. Suchan attaching member may swa the insulator 10, by the same motion puttingthe two cars 19 in overlapping position; and then he swings the two earstogether so that thelugs 21 project through the holes 22, with the holesin alinement. Then he inserts the attaching member25 through theseregistering holes 20 of the assembled unit composed of the two matingmembers 16 and the insulator 10.. If the attaching member is a screwhook, it may already have been screwed into the support on which thestrain insulator is'mounted.

When the device is thus assembled and mounted, it remains in place, withits various parts in proper relative position, under all conditionsencountered, and can only beta-ken down by direct intention. Theinterlocking provided by the attaching member 25 and the lugs 21 andholes 22 prevents the fingers 15 from being withdrawn from the bore ofthe insulator. Such withdrawal can only be obtained by first separatingthe attaching member 25 from the pair of members 16. If the wire thatthe insulator supports should break, the unit comprising the two members19 and the insulator 10 merely drops down by gravity, while remaining onthe hook 25,

without letting the insulator 10 fall off. If

the insulator 10 is broken for any reason, the

overlapping fingers 25 catch the wire which was fastened in the groove12 of the insulator, and thus keep it from falling.

I claim as my invention 1. Alstrain insulator mounting, comprising twomating members having fingers arranged to extend into an insulator borefrom opposite ends thereof; said two mating members being arranged tooverlap each other outside of said insulator, and the overlapping partsof said members being provided with registering holes for receiving anattaching member, the overlapping portions of said two mating membersbeing provided with inter-- locking parts for preventing relativeturning of said two members.

2. A strain insulator mounting, comprising two substantially similarmembers, each of said members having a head portion and a fingerportion, said finger portions being adapted to overlap, each of saidhead portions being provided with a locking lug and with a depressionfor receiving the locking lug on the other of said members.

8. A strain insulator mounting, comprising two mating members adapted tobe assembled in. substantially coplanar relation, said two'membershaving portions which owrlap when the members are assembled, saidoverlapping portions being provided with locking means for preventingrelative movement of said two members in their plane, and said membershaving extending portions adapted to receive and hold between them aninsulator. V

1. A strain insulator mounting as set forth in claim 3 with the additionthat the overlapping portions of said members are provided withregistering holes for receiving an attaching member.

In witness whereof, I have hereunto my hand at Indianapolis, Indiana,this 2d day of August, A. D. one thousand nine hundred and twenty-four.

WILLIAM H. PEARL.

